The Pyrenees are changing, and their species are already showing signs of it. Among them is the water pipit (Anthus spinoletta), a common bird in the mountain range’s alpine grasslands, which is living at increasingly higher altitudes, possibly due to climate change. This shift to higher elevations reduces the extent of its available habitat and increases its vulnerability. Signs like this are being shown by several sentinel species in the Pyrenean bioregion, a pattern that is being studied by the INBIOPYR project.

Funded by the Interreg POCTEFA programme and led by the Aranzadi Science Society, the cross-border project’s main objective is to help harmonize the cross-border collection of wildlife data and the development of indicators that measure the scale of change in the spatial and temporal distribution of Pyrenean sentinel species that are sensitive to climate change. The project also involves the Conservatory of Natural Areas of Ariège, the Catalan Institute of Ornithology, the League for the Protection of Birds, the Pyrenean Climate Change Observatory, and the Ordesa-Viñamala Biosphere Reserve.

Dentro del trabajo realizado en el marco de INBIOPYR, un seminario celebrado el pasado 11 de marzo en Foix (Francia) permitió analizar la fauna centinela a través de indicadores del cambio de la abundancia y la presencia de las especies en el espacio y en el tiempo. Tal y como expuso Esther Güiza Marquez, gestora de proyectos del Observatorio Pirenaico del Cambio Climático, “estos cambios se pueden relacionar con los indicadores climáticos y ser utilizados como herramientas para analizar los efectos del cambio climático en la biodiversidad de los Pirineos”. Durante el seminario se pudieron observar los primeros resultados que arrojan esas especies centinela, aquellas que actúan como indicadores d e las consecuencias del cambio climático en los ecosistemas de montaña.

Las aves, uno de los indicadores más claros

The water pipit (Anthus spinoletta) is one of the few birds adapted to high mountain environments. However, data collected over the last 15 years on the Faunpyr portal—which gathers wildlife observations made throughout the mountain range—indicate that it is being detected each year at a higher average altitude, suggesting that its natural habitat is also shifting to higher elevations. “This shift in a species that already lives in the highest areas may prove critical for its survival and warns us that, before long, it may no longer find areas where it can complete its life cycle,” says Marc Anton, researcher and monitoring and follow-up project technician at the Catalan Institute of Ornithology (ICO).

This change can also be seen in other bird species that currently live at lower elevations. In the case of the common cuckoo (Cuculus canorus), models of the probability of this species occurring at altitude show an increase in the likelihood of it being observed at higher elevations, to the detriment of the probability of it being found at lower altitudes.

This altitudinal shift of the common cuckoo is also reflected in its abundance. Specifically, the species shows a trend toward lower abundance in low mountain areas, remains stable in mid-mountain areas, and tends to be more abundant in high-mountain environments.

Changes are not only being observed in altitude.

Phenological studies—which analyze the cycles and key dates in the lives of living organisms throughout the year—also show changes that may be due to climate change. Observations of the Apollo butterfly (Parnassius apollo) over five-year periods suggest that the species has brought forward its appearance, with the peak frequency of observations occurring increasingly earlier over the last five years.

In this context, according to Olatz Aizpurua, ornithologist at the Aranzadi Science Society, “the results obtained to date reinforce the importance of cross-border cooperation and long-term monitoring of sentinel species. The work carried out within the framework of INBIOPYR not only makes it possible to detect the effects of climate change on Pyrenean wildlife at an early stage, but will also lay the groundwork for improving decision-making in the field of conservation.”